Tire-tread.



paran ara THOMAS B. TEFENBACHER, or New YORK, n. Y.

TIRE-TREAVD.

Specification of Letters Patent.

Patented Nov. 23, 1915 Application filed September 5, 1914. Serial No.860,435.

T0 all whom it may concern:

Be it known that I,'T11oMAs B. TmrnN- BACHER, a citizen of the UnitedStates, and resident of the borough of Manhattan, city and State of NewYork, have invented certain new and useful Improvements in Tiref Treads,of which the following is a specification. l

This invention relates to tire-treads, and has for its object to providean improved tread, which will, by its application to a tire,'bring aboutan even distribution of the Wear upon the same, and thereby prolong thelife of the tire.

Hitherto in the use of tires of well known make, the peripheral portionthereof, forming the'tread, was usually made of rubber, and this becameworn from a rounded portion to a fiat portion, and .thereafter anypressure exerted on the flattened portion would cause the various layersof fabric forming part of the tire to be pressed ra dially inwardly outof their curved normal position to la attened or abnormal position. Thisattening of the layers of fabric would cause friction of one layer onanother, and would soon result in deterioration of the tire.

The object of this invention is to overcome this disadvantage, and toprovide a tread which, when applied to tires of any ordinary or wellknown make, will have a iiat exterior surface, and be worn flatthereafter, and as thus worn flat will not cause the curved part of thetire to be pressedinwardly and subjcted to the disadvantageousfrictional action referred to, and the excessive kneading of the rubberin all directions.

In the accompanying drawing, Figure 1 is a vertical section of a tire ofapproved make, having applied thereto a tread embodying the invention,Fig, 2 is a section of the tread before it is placed on the tire, and

.Fig 3 is a section of the tread showing the layers of fabric formingthe same arranged in a different manner from the arrangement shown inFigs. 1 and 2.

Similar reference numerals indicate corresponding parts throughout thevarious views.

`Referring to the drawing, and'more Aparticularly to Fig. 1, the rim 10is of the usual form, and instead of the particular form shown in Fig.l1, anypther approved form may be used. This rim supports .the beads 11and 12 of the tire 13, which tire has a circular cross-section and iscomposed of a plurality of layers or plies of fabric coacting withlayers 141 of rubber. The tire is shown conventionally in Fig. 1, and itis clear that any type of tire having a rounded periphery may be used.At the peripheral portion 15 ofthe tire 18, a layer 16 of rubber isprovided, on which is placed my improved. tread, which comprises aplurality of layers of fabric 18 of increasing width upwardly1 extendingfrom one side of the peripheral portion of the tire to the other sidethereof, and passing at either side over alining niembers 20 and 21, andextending at their free ends 22 and 23 below the layers 18. The aliningmembers 2O and 21 are preferably made of Sea Island cotton rope, andsaid ropes` 20 and 21 extend circumferentially around the entire tire,one at each side of a' the peripheral portion 15.' The ends 22 and 23 ofthe tread snugly iit against'the lowery portion of the layers 18, and asuitable quantity .of rubber, indicated4 by 26, serves te bind the endsQ2 and 23 to the layers 18, and lto the rope aiming-members 20 and 21,said rubber 26 filling all theinclosed space not filled by the rope. Thetread thus formed, as shown in Fig. 2, is then applied to the terior ofthe rubber layer 1G of the tire, and

a rubber layer 28, having a `flat tread portion 29 and downwardlyextending portions 30, is formed around the tread, so as to conrpletethe tire, and to protect the fabric 'lav ers of the tread. Zhen theimproved tread is thus applied to the tire, and secured 'there-` to, byvulcanizatien or other means, so as to become an integral part of thetire, the entire tire with the improved tread is ready te be used. Inuse, such an improved tire has the advantzge that all weight which is applied'to the tread portion 29 is evenly diA vided along the width of thesame, and conv` I sequently along the width of the layers and thecireumferentially-extending ropes 2" 20- and 21 serve to assist in theproper dis" tribution of the forces applied to the tread portion 29.The'rope portionsZO and 21 serve also to till in the gaps fornied bybending under of the ends of the layers 18, i,

`ways maintainsitscurved shape, and doesY not become iattened as in thetires-hitherto in use, and hence the various layersof fabric therein arenot caused 4to frictionally i Amove one in respect to the other, andthereby their deterioration is prevented. Thus, my improved tread,having the .parallel layers 18 with the bent-under portions at eitherside thereof, serves to uniformly take up the various forces, and byremaining constantly in flattened shape, it is not unequally pressedinwardly,""and so prevents the flattening of the curved peripheralportion l5.

In Fig. 3 is shown another embodiment of .L5 .my improved tread portion,which consists in having the layers 18a bent at the points 18b aroundthe ropes 20? and 21a. and eX- tended underneath the parallel -layers18a, being curved in substantially the same cur- 20 v'ature as theperipheral portion l5 of the tire. I This curvature is shown clearly inFig. 3, f and is indicated yby the character 30. An examination oftheembodiment shown in Fig. 3 shows clearly that any forces that areapplied to the parallel flat layers 181 are taken up thereby, and thosethat are transmitted to the curved portion of the tread are distributedtherein, bringing about a slight flattening of the layers forming thislowerportion, but by having the forces taken up'by the tread and thefiat portion '18a and the curved portion 230 thereon, these forces areprevented from exerting themselves on the peripheral portion 15, andthereby this peripheral portion l5 is not flattened, and does not havethe fabric layers thereof moved one in respect to the other, so as toproduce a frictional engagement with the various layers which generatesobjec- 40 tionable heat' and results in the rapid deterioration of thetire.

In the embodiment shown in the drawings, the inside diameter of thetread is substantiallythe same as the diameter of the tire at l theoutside thereof, and the transverse curvature of the inner face of thetread is the same as the transverse curvature of the rounded outerportion of the tire, so as to en able a certain frictional holdto beobtained 0 when the tread is applied to the main tire portion. The`purpose ofthe invention is thus seen to be to take oti' the center ofthe tire the uneven weight, and distribute it over the surface of thetread and the surface of the tire under the tread, whereby longer lifetoboth tire and tread is obtained, asthe Weight is uniformly distributedover the.

whole bottom facing surface of the tire.

The construction as shown will not allow the rubber to crowd the treadtoward the sides, as there is no decline toward the side of the tread,but the tread ends abruptly. The treadmay be made in sections instead ofcontinuously as shown in the drawings.

I have shown several embodiments of my medial portion, the sides lof thelayers ter- 75 minatingadjacent the lower face of the horizontal medialportion, and lying parallel therewith, whereby the bent-under portionsof the layers of fabric will` assume an arenate curvature.

2. The combination of a tire, and a tread member, comprising a pluralityof laminat-ed layers of fabric, the medial portion of the tread lyingtangentially with the periphery of the tire, stilfening membersenveloped by the side-portions of the tread, the free end portions ofthe layers adapted to conform to the outer configuration of the tire,and means for enveloping the tread member and the adjacent portion ofthe tire.

3. The combination with a tire, ofa. tread member, comprising aflattened portion formed of a plurality of layers of fabric, havingtheir ends bent under to form inwardly-extending portions curved toshape themselves to the peripheral exterior portion of the tire, aliningrope members enveloped by the Said end portions at the edges ofthe treadmembers, the extremities of the end portions terminating in substantialcontact with the fiattened portion at a point adjacent each other, and arubber filling interposed between the flattened portion and thebent-under ends of the tread.

4. The combination of a tire and a tread member, comprising a pluralityof superin1- posed layers of fabric, and each layer being of graduallyincreasing length relative to the'preceding layer, the layer forming the1.10 outermost one being the longest and the layers thereunder being`gradually and successively shorter to the shortest innermost layer, andhaving a. flattened portion and their endsbent under to form inwardlyex- 115 tending portions curved to shape themselves to the peripheralexterior -portion of the tire, and having the extremities of the endportions terminating in substantial contact with the under side of theflattened portion at 120 points adjacent to each other alongside theunderside of the fiattened portion and distancedfrom each other incorrespondence with the difference in lengths of the layers, and arubber covering surrounding the 125 layers, a portion of the rubbercoveringbeing between the tire and the tread portion.`

5. An improved tire tread, comprising a. plurality of superimposedlayers of fabric havinga Hattened portion wherein the layers 130 aresubstantially parallel,`the Vlayer forming the outermost one: being thelongest, and the layers thereunder being gradually and successivelyshorter to the shortestinnermost layer, and having,r their end portionsbent un. der to form curved inwardly extending portions, theextremitiesl of -the end portions terminatingalong a' straight line andin substantial Contact with thev innermost llayer of the flattenedportion, at points adjacent each other, and distanced from eachother 1ncorrespondence with 'the diferencia in lengths of the-layersztlhe endsof the longest layer meeting in'substantial contact at the centralportion of the flattened portion land 15 alining members at the ends ofthe flattened portions and enveloped by the said end portions.

In testimony, that I claim the foregoing as my invention, I have signedmy namein t0 presence of two subscribing Witnesses.l

A' THOMAS B. TIEFENBACHER.

Witnesses:

Jos, BISBAND, F. Hose.

